According to reduction in size of an ultrasonic diagnostic apparatus that easily provides a tomographic image of a subject as a real-time ultrasonic dynamic image, the ultrasonic diagnostic apparatus plays more important roles in various medical diagnoses and examinations at the places other than ultrasonic inspection rooms, such as bedsides in hospital wards, private clinics and health care support center in the offices, for example.
However, because of the limitation of the number of medical doctors as examiners who can perform diagnoses accurately from displayed ultrasonic dynamic images, the shortage of the medical doctors who can interpret ultrasonic images would be of concern in the case where the ultrasonic diagnostic apparatuses become prevalent as the demand for apparatuses for home medical care is expected to grow in the market in the future.
In addition, as speeds of communication networks represented by internets are increased, connections via communication lines have become possible in various fields. There is an expectation for the development of an ultrasonic diagnostic apparatus enabling a remote diagnosis that is connected to a hospital via a communication line, and can enable a medical doctor in the hospital to perform an accurate diagnosis, even when such a medical doctor is not present near the patient, for example, in the case where the acute patient is in, for example, an aircraft in flight, a watercraft under sail, a running train or the like, or in the case where the injured person is carried with an ambulance. As such an ultrasonic diagnostic apparatus, a remote ultrasonic diagnostic system utilizing a communication line (see, for example, Patent document 1) and the like are known.
As mentioned above, in recent years, a data rate that can be transmitted through a communication line such as an internet has been dramatically increased in speed, but has not reached a speed that enables transmission of an uncompressed real-time ultrasonic dynamic image generated by an ultrasonic diagnostic apparatus. Thus, in the above-described conventional example, transmission of the real-time ultrasonic dynamic image is performed by introducing a high-efficiency data compression method such as MPEG that can compress image information to have the data rate at an upper limit value or less of the communication line, and can suppress deterioration of an image to a minimum, thus making efforts to transmit a real-time ultrasonic dynamic image that is dose to the original image even when the data rate of the line is low.
In the remote ultrasonic diagnostic system, a hospital-side apparatus that receives an ultrasonic image is required to exclude factors that may affect a medical diagnosis negatively, such as degradation in image quality, a decrease in image size and a decrease in frame rate due to a speed of the communication line.
Patent document 1: JP 2002-17732 A